Telecommunications systems, cable television systems and data communication networks use optical networks to rapidly convey large amounts of information between remote points. In an optical network, information is conveyed in the form of optical signals through optical fibers. Optical fibers comprise thin strands of glass capable of communicating the signals over long distances with very low loss. Optical networks often employ wavelength division multiplexing (WDM) or dense wavelength division multiplexing (DWDM) to increase transmission capacity. In WDM and DWDM networks, a number of optical channels are carried in each fiber at disparate wavelengths, thereby increasing network capacity.
An optical signal comprised of disparate wavelengths experiences optical dispersion, a sometimes undesirable phenomenon that causes the separation of an optical wave into spectral components with different frequencies. Optical dispersion occurs because the different wavelengths propagate at different capacities. The separation of an optical wave into its respective channels due to optical dispersion requires optical dispersion compensation for the particular optical signal.
Optical networks use various transmission capacities and modulation techniques to transmit information. If a single network includes signals of different transmission capacities and modulation techniques, an optical dispersion technique designed for a specific transmission capacity and modulation technique may not provide appropriate compensation for the other transmission capacity and modulation technique in the network.